Kubernetes DaemonSet extensions/v1beta1 deprecated

[jfcgaspar]

As of Kubernetes release 1.16, DaemonSet in the extensions/v1beta1 is no longer available.
This breaks /gluster-kubernetes/deploy/kube-template/glusterfs-daemonset.yaml which still invokes this apiversion.

Should be migrated to apps/v1, with the following note:

"spec.selector is now required and immutable after creation; use the existing template labels as the selector for seamless upgrades"

https://kubernetes.io/blog/2019/07/18/api-deprecations-in-1-16/